# build/output directory
O        ?= build

# CPu type
MCU      ?= atmega2560

# project name
PROJECT   = NMES

CSRC     := $(shell find src/ -name '*.c')
CXXSRC   := $(shell find src/ -name '*.cpp')
ASRC     := $(shell find src/ -name '*.S')

INC      := $(shell find src/ -type d)

LIBRARIES = m

OBJ      := $(patsubst %.S,$(O)/%.o,$(notdir $(ASRC))) $(patsubst %.c,$(O)/%.o,$(notdir $(CSRC))) $(patsubst %.cpp,$(O)/%.o,$(notdir $(CXXSRC)))
DEP      := $(patsubst %o,%d,$(OBJ))

TOOLCHAIN_PATH =
ARCH     ?= avr
PREFIX    = $(ARCH)-

OPTIMIZE := s

FLAGS    += -O$(OPTIMIZE)
FLAGS    += -ffunction-sections -fdata-sections
FLAGS    += -Wall -g
FLAGS    += -funsigned-char -funsigned-bitfields -fshort-enums
FLAGS    += $(patsubst %,-I%,$(INC))
FLAGS    += $(patsubst %,-D%,$(CDEFS))

FLAGS    += -DF_CPU=$(F_CPU)
FLAGS    += -DBAUD=$(APPBAUD)
FLAGS    += -DXONXOFF
FLAGS    += -mmcu=$(MCU)
FLAGS    += -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -finline-functions-called-once

CFLAGS   += $(FLAGS) -std=gnu11 -pipe

ASFLAGS  += $(FLAGS)

CXXFLAGS += $(FLAGS) -fno-rtti -fno-exceptions -std=gnu++11 -pipe

LDFLAGS  += $(FLAGS) -Wl,--as-needed,--gc-sections
LDFLAGS  += -Wl,-Map=$(O)/$(PROJECT).map

LIBS     += $(patsubst %,-l%,$(LIBRARIES))

CONSOLE  ?= /dev/arduino
BAUD     ?= 115200
PROGRAMMER ?= stk500v2
F_CPU    ?= 16000000UL

APPBAUD  ?= 500000

###

# depend on eigen3
# CFLAGS   += $(shell pkg-config --cflags eigen3)
# LIBS     += $(shell pkg-config --libs eigen3)

###

VPATH     = $(O) $(shell find src/ -type d)

CC        = $(TOOLCHAIN_PATH)$(PREFIX)gcc
CXX       = $(TOOLCHAIN_PATH)$(PREFIX)g++
OBJCOPY   = $(TOOLCHAIN_PATH)$(PREFIX)objcopy
OBJDUMP   = $(TOOLCHAIN_PATH)$(PREFIX)objdump
AR        = $(TOOLCHAIN_PATH)$(PREFIX)ar
SIZE      = $(TOOLCHAIN_PATH)$(PREFIX)size
READELF   = $(TOOLCHAIN_PATH)$(PREFIX)readelf
NM        = $(TOOLCHAIN_PATH)$(PREFIX)nm
RM        = rm -f
RMDIR     = rmdir
MKDIR     = mkdir -p


.PHONY: all clean run flash functionsbysize

.PRECIOUS: $(O)/%.o $(O)/%.elf

all: $(O)/$(PROJECT).hex

clean:
	$(RM) $(O)/$(PROJECT).hex $(O)/$(PROJECT).elf
	$(RM) $(OBJ)
	$(RM) $(DEP)
	$(RM) $(O)/$(PROJECT).map
	$(RMDIR) $(O)

flash: $(O)/$(PROJECT).hex
	avrdude -c$(PROGRAMMER) -b$(BAUD) -p$(MCU) -P$(CONSOLE) -U flash:w:$<

functionsbysize: $(OBJ)
	@$(OBJDUMP) -h $^ | grep '\.text\.' | perl -ne '/\.text\.(\S+)\s+([0-9a-f]+)/ && printf "%u\t%s\n", eval("0x$$2"), $$1;' | sort -n

$(O):
	$(MKDIR) $(O)

$(O)/%.hex: $(O)/%.elf | $(O)
	@echo "  COPY  " $@
	@$(OBJCOPY) -j .text -j .data -j .rodata -O ihex $< $@

$(O)/%.elf: $(OBJ) | $(O)
	@echo "  LINK  " $@
	@$(CXX) $(LDFLAGS) -o $@ $^ $(LIBS)

$(O)/%.o: %.cpp | $(O)
	@echo "  CXX   " $@
	@$(CXX) $(CXXFLAGS) -c -o $@ $^

$(O)/%.o: %.c | $(O)
	@echo "  CC    " $@
	@$(CC) $(CFLAGS) -c -o $@ $^

$(O)/%.o: $.S | $(O)
	@echo "  AS    " $@
	@$(AS) $(ASFLAGS) -c -o $@ $^

#autodep

$(O)/%.d: %.cpp | $(O)
	@echo "  DEP   " $@
	@$(CXX) -MM $(CXXFLAGS) $< | sed -e 's!\($*\)\.o[ :]+!\1.o \1.d:!' > $@

$(O)/%.d: %.c | $(O)
	@echo "  DEP   " $@
	@$(CC) -MM $(CFLAGS) $< | sed -e 's!\($*\)\.o[ :]+!\1.o \1.d:!' > $@

include $(DEP)